Growing Rosemary in Garissa
Soil suitability analysis based on Garissa's nutrient profile
Generally not ideal — Garissa is poorly suited to Rosemary. Garissa's soil (pH 7.96, alkaline) gives Rosemary a suitability score of 2/100. Match fertilizer to Garissa's nitrogen and phosphorus levels for the best result.
Garissa County is a challenging environment for Rosemary (soil-match score 2/100) and will need significant amendment before planting. Local soils average pH 7.96 — alkaline and inside the 6–8 band Rosemary prefers, so no lime is usually required. The main gap is nitrogen — measured at N 0.61 g/kg, P 37.7 mg/kg, K 407 mg/kg against this crop's medium/medium/medium demand — so the fertilizer plan below prioritises closing that deficit. The county's predominantly sandy soils suit Rosemary, which favours sandy loam. Garissa receives approximately 250 mm/year — well below Rosemary's minimum of 400 mm — so supplemental irrigation would be essential for this crop. On ShambaIQ's soil-match model, Rosemary is the #64 soil match of the 106 crops we assess for Garissa County. Rosemary's full potential is about 2,500 kg/acre (~KES 375,000/acre at KES 150/kg), but at Garissa's 2/100 suitability a realistic target here is closer to 63 kg/acre (~KES 9,450/acre) unless the constraints above are addressed.
Better matched to Garissa's soil: Sisal, Aloe Vera, and Green Grams — each scores higher on the same soil.
Soil & climate match
| Factor | Garissa soil | Rosemary needs | Status |
|---|---|---|---|
| pH | 7.96 | 6–8 | OK |
| Nitrogen | 0.61 g/kg | min 0.8 g/kg | Low |
| Phosphorus | 37.7 mg/kg | min 12 mg/kg | OK |
| Potassium | 407 mg/kg | min 150 mg/kg | OK |
| Rainfall | 250 mm | 400–900 mm | Low |
| Altitude | 200 m | 800–2,400 m | Low |
Planting calendar for Garissa
Long Rains· March–May
Short Rains· October–DecemberMain season here
Top dressing guide
Garissa's nitrogen (0.61 g/kg) is 76% of the 0.8 g/kg Rosemary needs, so the standard 0.2 bags/acre is raised to 0.25. Split it across two applications to limit leaching.
Economics
Fertilizer prices
Green = subsidized · (Commercial) per 50kg bag